Many companies have a Q&A database accumulating examples of questions and answers (hereinafter, Q&A) regarding their own products, so that users can access the Q&A database via the Internet. A Q&A database is to be constructed so that users can obtain satisfactory answers. That is to say, when a user inputs a question of a certain category, a satisfactory answer for the user is to be extracted in response to the question. Thus, Q&A examples including pairs of questions and answers are preferably classified into appropriate categories.
There is proposed a question and answer search system including an example database and a refined keyword selection unit. The example database stores examples of pairs of questions and answers. The refined keyword selection unit calculates the importance of keywords included in an example question based on the similarity between answers that are paired with the question, and selects a refined keyword from among the keywords for identifying the answer to the question according to the calculated importance.
Furthermore, there is proposed an expert selection method including the steps of receiving a question from a first user; determining the category related to the question; providing the question onto a predetermined web page; receiving an answer to the question from a second user; increasing the number of answers that are related to the second user and that correspond to the category in response to the answer being input; increasing the number of answer adoptions that are related to the second user and that correspond to the category if the answer is selected by the first user; computing a point related to the second user that corresponds to the category on the basis of an evaluation material including the number of answers and the number of answer adoptions; and selecting the second user, who meets a predetermined condition based on the point, as an expert of a relevant field in the category.
Patent document 1: Japanese Laid-Open Patent Publication No. 2010-009471
Japanese National Publication of International Patent Application No. 2006-524370
Examples of Q&A are manually classified into appropriate categories by the operator of the Q&A database. To actually classify the examples, either one of the following methods may be performed. One method involves actually reading the questions and answers and classifying them. Another method involves extracting keywords from character strings in the body text of questions and the body text of answers, and classifying the examples based on the extracted keywords.
However, it takes a significant amount of time and effort for the operator to classify the Q&A examples. Thus, the operation of updating the categories into which the examples have already been classified is virtually difficult, or this operation can only be executed after a significant amount of time has elapsed. Consequently, the Q&A examples belonging to the categories become outdated. Furthermore, the categories themselves may become obsolete. If the categories become obsolete, new Q&A examples cannot be classified into any of the existing categories. Furthermore, the relationship between the categories and the Q&A examples, i.e., the appropriateness of category classification, may not be congruous with the user's assumptions.